Biodiesel B20 vs Diesel 2: Is B20 Diesel Bad For Your Truck?

It will depend on the engine and who made it. For example, according to Cummins, a good portion of their engines can work with Bio20 fuel. This is from their 2023 FAQ web page. There may be other diesel makers that will say the same thing.

About the only problems that seem to have arisen over the years is that you may have a fuel filter problem. The B20 biodiesel fuel is better than the ultra-low sulfur fuels many oil makers produce. This fuel may also clean out your engine which will clog your fuel filter.

To learn more about this issue, just continue to read our article. It explores the topic so you have the best information possible to determine if you should use this fuel regularly or not. Take some time and see how this important information helps you make a good fuel-buying decision.

What is B20 Diesel?


Most of the time when you ask this question, you will get the answer that B20 is a blend of biodiesel and diesel #2 fuel. But what they do not say is what is in B20 fuel. Many websites talking about this topic leave out the ingredients used to make biodiesel.

The main ingredient in this alternative fuel is soybean oil, but that is just one ingredient. Other ingredients include restaurant grease, animal tallow, canola, and algae.

The word is that if you go with B20, you will get between 1 and 2% LESS performance, mileage-wise, out of your vehicle. That means that if you get 20 mpg with #2 diesel, you should get up to 19 with B20. There is not supposed to be a large amount of difference performance-wise between these two fuels.

Is B20 Diesel Bad?

This fuel is only bad for those diesel engines made prior to 1999 approx. Because government emission regulations keep changing, something had to be done about the emissions that come from diesel fuel.

Over the years, biodiesel fuel has gone through many processes to become compatible with those regulations. As far as our research has found, this fuel is not bad for diesel engines made in the year 2000 forward.

In fact, Cummins has stated in its FAQ page the many engines it has made over the years that will run on this fuel. There is one engine ISM CM570 that was built after 2002 that can run on this fuel. The rest you can look up at this link.

The information comes from the question of What Cummins engines can be used with B20 fuel. We will try to get more diesel engine brands listed that do the same thing.

What is The Problem With B20 Fuel?

The problems that are related to this food have nothing to do with performance per se. They have more to do with the bio origination than anything else.

The quality of the feedstock is one issue and then the shelf life for this fuel is shorter than #2 diesel. That means gas stations have to sell it quickly to make sure it remains good.

Other problems include that this fuel can break down faster than #2 and since it is made with biological materials, it suffers from biological contaminants. Finally, it is not a great fuel when the temperatures drop below 20 degrees F. it can gel and not flow too well when it is cold out.

One person posted on a discussion forum that he used B20 and it ruined his fuel system to the tune of almost $14,000 in repair. But that has not been verified as of yet.

Biodiesel B20 vs Diesel 2

In winter, the #2 is going to be the winner hands down. There is no competition here as the biofuel is vulnerable to cold weather problems that cause it to gel and not be in true liquid form.

In the warmer months of the year, including a couple of Fall months, then it would be a toss-up between which fuel is better. Both work well in the Summer, etc., and you may not see any difference in your performance.

Many owners have reported not seeing any real difference between the two fuels. But the big difference will be in the shelf life as well as the possibility of bacterial growth. The former fuel has those problems and the latter does not.

It is going to be a matter of preference and availability of which fuel you choose to run in your diesel vehicle. You may not get much choice if the gas stations are selling B5 to B20 without sticking any notices on their pumps.

B20 vs B5 Diesel


The biggest difference between these two fuels is the 15% more diesel in B5 than in B20. That will help with lubrication immensely. Diesel fuel is a lubricant and it needs its sulfur to work right.

B20 has less of both so you may have to use an additive in your fuel to make sure your engine gets the lubrication it needs. The additives would restore the sulfur levels to pre-ULSD rates making your diesel engine run better.

This is a big problem with these biodiesel fuels. They are low on sulfur so your older engine may not like this and not work as well. You do have to be careful with older engines as they were not originally designed to handle this fuel alternative.

It is going to be a toss-up as people feel B5 is better than B20 even though neither should harm your diesel engine.

B20 vs Diesel CO2 Emissions

According to one chart, the emissions for B20 go down between 10 and 20%. It is a fact that you will have fewer emissions from B20 than you will from regular diesel.

The only emission that may not go down is the NOx. According to the same chart, it went up as the Bio ingredients went up. You can check the chart at this link to see for yourselves.

Also, B20 is supposed to have a higher oxygen level than diesel #2. This ingredient helps reduce emissions somewhat and should help the fuel combust better.

It is not so much the emissions savings but the quality of those bio ingredients that will make the difference. The last word is that there are no national standards for the quality of the bio ingredients but that may have changed over recent years.

If the bio ingredients are top quality, then it should be a bit better fuel for the environment.

What is B20 Diesel Compatible?

You are going to find that the many different auto and truck makers have produced lines of vehicles that are compatible with this fuel alternative. GM and Chevy are just two of them and they started around 2017.

Those vehicles include the Silverado, Sierra, Express, the Savana, the Cruze, and other GM-made cars and trucks. Audi has a couple of their mid-size cars working with B20 fuel.

The Volkswagen Beetle and Jetta (certain models) are also equipped with biodiesel-friendly diesel motors. Then there is the Jeep Grand Cherokee and the Ford Transit that will work with this fuel.

Finally, the RAM ecodiesel is among this group. This is not an exhaustive list as Cummins has a long list of motors, that will work with this fuel. Most of those motors were built after 2007

Can I Use B20 Diesel in My Truck?

The answer is yes you can as it seems that the B5 to 20 fuels have great lubrication for those diesel engines. Owners have been reporting that they have been using these fuels in their pre-2012 vehicles without any problems.

It is 80% diesel #2 fuel so you are not missing out on much of what diesel fuel offers diesel engines. B5 is probably a better fuel to use since it is 95% diesel #2. You may have problems with your fuel filters though. At least the first few fill-ups.

It has been said that B20 can clean out the engine and really clog up that filter. Or it has a lot of bio gunk in it that does the same thing. Some owners have been reporting that they have changed their fuel filters several times when they first started using this fuel.

Can I Use B20 Diesel in a Mercedes Sprinter?

This is a product of an ever-changing mind. At first Mercedes Benz said to avoid all biofuels. Then it said that up to B5 is okay and finally it has been reported that the company has okayed B20 in emergencies.

But that news is as of 2020. It is also news that we reported when we dedicated a whole article to this vehicle. You can read about our results here: Can I use biodiesel in my Mercedes Sprinter.

Mercedes Benz does not seem to be the type of car company that likes to keep up with changing attitudes when it comes to emissions. They would prefer that you stuck with diesel #2 without the bio additives as they say your fuel system will get damaged if you use the B5+ fuels.

Mercedes has also said in the past that any car owner using B6 or higher in their fuel tank will not have any warranty protection over any damage caused by those fuel options.

We have not heard if they have changed their minds on this stance or not. They have also said, it is okay to use B20 as long as you refill the tank as soon as you find a gas station with the lower fuel options (Diesel #2 & B5).

Can I Use B20 Diesel in My Duramax?

GM announces B20 biofuel capability for Duramax turbo diesel” this is the title of a news release that was published some time ago. There is no date on the article telling everyone when it was written but the contents talk about 2011 vehicles.

The first two paragraphs include the following words- “ General Motors announced on February 8 that its new lineup of heavy-duty diesel pickups will have B20 biodiesel capability.

B20 fuel is a blend of 20 percent biodiesel and 80 percent conventional diesel, which helps lower carbon dioxide emissions and lessens dependence on petroleum. The announcement was made at the National Biodiesel Conference.

GM's new Duramax 6.6-liter turbo diesel engine has been substantially revised to include B20 capability, as well as meet strict new emissions standards effective this year.”

So the answer should be yes unless anything has changed since that announcement and today. Then since this article was written prior to Feb. 8th, we know they are not talking about this year.

B20 Diesel in 6.7 Cummins

This was a problem about 10 years ago when the Biofuels first started coming out. Many of the states were making it mandatory that their gas stations sell B5 and B20 biodiesel fuel only. Owners were concerned back then and wrote Dodge about this problem.

Their response at that time was: “ Our current Cummins’ is rated for up to B20. The downside is, you may decrease your oil change intervals. Pay attention to your oil level. If you notice your oil level INCREASING, it’s time to change your oil.

It is normal for some amount of fuel to wash down the cylinder and get into the oil. The bio component of the fuel evaporates at a higher temperature than the petro component.

So, if the engine does not get good and warm and driven for a sufficient amount of time, not all of the bio component in the oil will evaporate and it will actually appear that the oil level is increasing.” (source)

If you read the link we included earlier, you will find the long list of Cummins engines that were compatible with Biodiesel since 2007. As far as we know, nothing has changed.

B20 Diesel in 6.0 Powerstroke

There should be no problem with switching fuels if you haven’t done so already. This was an issue 17 years ago when biodiesel fuels were first coming out and owners back them have reported little to no problems with their engines.

The same issues, clogged fuel filters, and injectors, today were the same issues back then. In 2011, different owners were saying it was okay to run B100 in the 6.0 Powerstroke but that seems a bit stretched.

In 2009, they were recommending B20 as long as you kept a new fuel filter handy. You may also experience some power loss.

B20 Diesel Cost


As of 2022, B20 was cheaper than diesel #2. But not by much. It was only a few cents lower than regular diesel and it may depend on your gas station if it remains lower or not.

The surprising statistic is that B99 is far more expensive than either B20 or Diesel #2. It is a good 50 cents approx., more expensive than those two fuels. But prices change on almost a daily basis so it is hard to gauge what the price will be next week.

If you want to read the specific details and get specific prices, then click here.

B20 Diesel Color

The color of diesel fuel, any type, can get confusing as there are so many different colors used today. Red as you know is the farm diesel that is not taxed and is illegal to use in street vehicles.

Blue can be added as well and it is for tax-free diesel also. Then you may see brown with a green tint which is not supposed to be used in street vehicles either. Regular diesel is supposed to be clear and sometimes it is a yellow color.

Biodiesel fuel is supposed to be gold but it can also be brown.

Who Sells B20 Diesel?

The best way to answer this question is to look at the pump. If the gas station is selling B6- B20 then the pump must be labeled with the B6- B20 sticker. There will be no sticker on any pump that sells B1 to B5 biodiesel fuel.

It is to be handled like diesel #2. B20+ and B100 must be clearly labeled at the pump. It is hard to say which gas stations are selling this fuel but most are selling B5.

This is not the time to go into automatic mode as you may pump something you do not want in your gas tank. Even though B20 is cheaper, it is not recommended by all car makers.

Some Final Words

B20 or any biodiesel fuel is being touted by the government as the next best fuel source. That is because it helps the environment as well as reduces the country’s dependency on foreign oil.

The good news is that this fuel should only hurt your injectors and fuel filters. Other than that it is a very safe fuel to use. There have been no verified horror stories even when using these fuel alternatives long-term.

Just go with your manufacturer's recommendation if you are not sure. It is in the owner’s manual.

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